Abrading disc or head



0st. 4, 1955 1.. K. SINGLEY ABRADING DISC OR HEAD Filed Nov. 5, 1954INVENTOR Lzsua KSINGLEY ATTORNEY ABRADTNG iBlSC (BR HEAD K. Singley,Hendersonviile, N. C.

Application November 3, 1954, Serial No. 466,517

6 Claims. (01. 51-197) The present invention relates to an abrading orsanding disc or head for use on power tools and the like.

A primary object of the invention is to provide an improved sanding discfor use upon a drill press or the like and designed particularly tofacilitate the use of standard square sand paper, abrading cloth and thelike.

Another object is to provide novel and simplified means for readilydetachably securing the square abrading sheet to the disc, in a mannerso that the sheet will be securely held in place at its four corners.

A further object is to provide an abrading disc or head for rotary powertools which is octagonal so that the four corner portions of theabrading sheet, which is square, may be turned up and over alternatemarginal edge portions of the disc.

Another object is to provide simplified clamping means for securing thecorner portions of the abrading or sanding sheet in place upon the disc,and including adjusting nuts which are restrained against separationfrom their screwthreaded studs, so that they cannot fly off of the studsduring the operation of the same.

Other objects and advantages of the invention will be apparent duringthe course of the following description.

In the accompanying drawings, forming a part of this application, and inwhich like numerals are employed to designate like parts throughout thesame,

Figure l is a plan view of a sanding disc or head embodying myinvention,

Figure 2 is a side elevation of the same,

Figure 3 is an enlarged fragmentary central vertical section taken online 3-3 of Figure 1,

Figure 4 is an enlarged vertical section taken on line d-- iof Figure l,and,

Figure 5 is a further plan view of the device on a reduced scale showingthe position of the square abrading sheet and the clamps, prior tosecuring the four corners of the sheet to the disc.

in the drawings, where for the purpose of illustration is shown apreferred embodiment of the invention, the numeral designates generallya flat disc or plate of wood, plastics material, fibre board or thelike. The disc is substantially rigid or stiff, and may be ofconsiderable thickness, as shown. The flat disc 10 is octagonal in shapeto facilitate using square sheets of sand paper or other suitableabrading material with the same, as will be fully explained. The lowersurface of the disc 10 is preferably entirely covered by a resilient pad11 of sponge rubber or the like, although felt or other suitablematerial may be used for the pad 11 if preferred. The pad 11 is ofcourse also octagonal.

A metal hub 12 is arranged centrally upon the opposite side of the discill, and includes a mounting flange 13, integral therewith, and rigidlysecured to the disc it by suitable screws il or the like. An adapter pinor shaft 15 is detachably rigidly secured within the bore of the hub 12by means of a set screw 16, or the like. The adapter pin i5 is readilyengageable within the chuck of a drill press or similar power tool usedto impart rotation to the tes Patent 0 2,719,38 9 Patented ct. 4, 1955disc lltl during its use. I also intend making the bore of the hub 12screw threaded for receiving a screw-threaded shaft or spindle of apower tool or motor, in which case the adapter pin 15' and set screw 16will not be employed. Any other suitable or conventional means ofconnecting the disc ill with a power tool may be employed if preferred.

The disc id is provided just inwardly of and parallel to alternatemarginal edge portions 17 of the disc and in the upper face thereof withgrooves or recesses 18, as shown. These grooves are four in number andelongated so as to extend along a considerable portion of the lengths ofthe adjacent marginal edge portions 17. The grooves or slots 18 arepreferably arcuate or rounded longitudinally and transversely, as shownin the drawings, but they can be formed square in cross section orotherwise if pre ferred.

inwardly of and at the longitudinal center of each groove 18, the discIll is provided with an opening 19 extending therethrough andcounterbored in the lower side of the disc til as shown at 20. Upwardlydirected screw threaded bolts or studs 21 extend through the openings19, and include square or polygonal heads 22, which are received by thecounterbores 20, such counterbores being of the same shape as the heads22 to prevent the studs 21 from turning. The upper screw-threaded endsof the studs 21 project a considerable distance above the top face ofthe disc 10, as shown. Winged nuts 23 are carried by the studs 21 abovethe disc lit, and the upper ends of the studs are scored or staked at 24to prevent separation of the nuts 23 from the studs 21 during rotationof the disc.

Four L-shaped clamps or clips 25 are provided, and each of these clampshas an opening in its fiat horizontal portion 25 receiving a stud 21, asshown. Each stud 21 is arranged at the longitudinal center of theportion 26 of the clamp. The clamps 25 are loosely mounted upon thestuds 21 prior to the tightening of the wing nuts 23. Each L-shapedclamp 25 further comprises a depending or vertical extension 27,integral therewith and projecting into the adjacent groove 18 andextending to the bottom of the groove. The extension 27 is slightlylonger than the depth of the groove 18, so that when the nut 23 isturned downwardly into clamping engagement with the portion 26, theouter end portion of the clamp will remain elevated somewhat from thetop surface of the disc :10, as clearly shown in Figures 2 and 3. Thestuds 21 are sulficiently long so that when the nuts 23 are loosened,the extensions 27 may be disengaged from the grooves in, thus permittingthe clamps 25 to be turned upon the studs 21 to positions parallel withthe grooves 113, as shown in Figure 5.

A square sheet 23 of sand paper, emery cloth or other suitable abradingmaterial is used in conjunction with the octagonal disc ill. As shown inFigure 5, the disc it and associated elements is placed upon the sheet28 of sand paper with the four corner portions 29 thereof arrangedadjacent to the marginal edges 17 of the disc having the grooves 18. Thenuts 23 are loosened, and the clamps 25 are turned to positionsgenerally parallel with the grooves as shown in Figure 5. The cornerportions 29 of the abrading sheet 28 are now folded upwardly and aboutthe adjacent edges 17" of the disc and over the grooves 18, as bestshown in Figure l. The clamps 25 are now returned to their positionsshown in Figure 1, wherein the extensions 27 center the grooves 18 andengage upon the corner portions 29 of the sand paper. The winged nuts 23are now tightened into clamping relation with the portions 26, and thisforces the depending extensions 2.7 into clamping engagement with thecorner portions of the sandpaper, which corner portions are now securelyheld by the extensions 27 against the bottoms of the grooves 18. Theextreme corners or points of the portions 29 now underlie the clampportions 26 as indi cated at 30. The arrangement provides for renderingthe abrasive sheet 28 taut against the resilient pad 11; as the cornerportions 29 are drawn downwardly into the grooves 18 by the clamps 25.Once the clamps are set, the abrading sheet 28 is securely held andcannot turn or slip relative to the disc 16. The marginal edges of thesquare sheet 28 may be flush with the marginal edges 17 of the discbetween the grooves 18, as shown in Figure 5. The arrangement is neat inappearance and compact, and standard sizes of square sand paper sheetsmay be readily used. Obviously, it is a simple matter to remove orreplace the abrasive sheet 28.

It is to be understood that the form of the invention herewith shown anddescribed is to be taken as a preferred example of the same, and thatvarious changes in the shape, size and arrangement of parts may beresorted to, without departing from the spirit of the invention or scopeof the subjoined claims.

Having thus described my invention, I claim:

1. An abrading device comprising a polygonal disc, said disc beingprovided in one face and near and inwardly of marginal edge portionsthereof with recesses, clamps carried by the disc adjacent to saidrecesses and including portions engagable within the recesses, meansconnected with the cl ps for forcing said portions of the clamps againstthe bottoms of the recesses, a polygonal abrading sheet to extend overthe face of the disc remote from the clamps and recesses and havingcorner portions, said corner portions being foldable about the marginaledge portions of the disc adjacent the recesses and over the recesses sothat the portions of the clamps which enter the recesses may force saidcorner portions into clamping engagement with the bottoms of therecesses, and means for attaching the disc to the spindle of a powertool or the like.

2. An abrading device comprising a polygonal disc, said disc beingprovided in one face thereof and near marginal edge portions of the samewith grooves extending substantially parallel to said edge portions,screw threaded elements secured to the disc near and inwardly of saidgrooves, nuts mounted upon the screw-threaded elements, substantiallyL-shaped clamps connected with the screw threaded elements and havingparts engagable within the grooves, a polygonal sheet of abradingmaterial extending over the other face of the disc and having cornerportions foldable about the marginal edges of the disc adjacent thegrooves, said corner portions extending over the grooves and beneathsaid parts of the clamps which enter the grooves, and means forconnecting the disc to a rotary power tool or the like.

3. An abrading device comprising a substantially rigid octagonal disc,said disc being provided in one face and near and inwardly of alternatemarginal edge portions with grooves, screw-threaded studs secured to thedisc inwardly of said grooves and extending above the disc, nuts carriedby the screw-threaded studs, means for preventing the nuts fromcompletely disengaging said studs, clamp elements connected with thestuds between the disc and nuts and having parts engagable within thegrooves and adapted to contact the bottoms of the grooves when the nutsare turned into engagement with the clamp elements, whereby the clampelements may engage and clamp the corner portions of a rectangularabrading sheet within the grooves when the sheet is extended over theface of the disc remote from the grooves, and means for connecting thedisc with a rotary element.

4. An abrading device comprising an octagonal disc, said disc beingprovided in one side and near and inwardly of alternate marginal edgesof the disc with elongated grooves extending generally parallel withsaid marginal edges, said grooves being arcuate longitudinally and intransverse section, screw threaded elements carried by the disc near andinwardly of the grooves, nuts mounted upon the screw threaded elements,L-shaped clamps connected with the screw-threaded elements between thenuts and disc and being engagable within the grooves, a rectangularsheet of sand paper covering the other side of the disc and havingcorner portions foldable about the marginal edges of the disc adjacentthe grooves, said corner portions extending across the grooves and undersaid clamps, whereby the clamps securely hold said corner portionsagainst the bottoms of the grooves, and means for connecting the discwith a rotary element.

5. An abrading device comprising a disc, said disc having a plurality ofsubstantially straight marginal edge portions, said disc being providedin one side thereof and near and inwardly of said straight marginal edgeportions with a corresponding number of recesses, an abrading sheethaving corner portions extending over the side of the disc remote fromsaid recesses, said corner portions being foldable about the straightmarginal edge portions of the disc into overlying relationship with therecesses in said one side of the disc, a plurality of separate clampingmeans connected with the disc near said recesses and having partsentering the recesses and forcing said corner portions of the abradingsheet into clamping engagement with the bottoms of the recesses, andmeans to support and drive the disc.

6. An abrading device comprising an octagonal disc having substantiallystraight edge portions and upper and lower faces, a substantially squareabrading sheet folded at its corners to provide flap portions, said flapportions engaging against certain of the substantially straight edgesand extending over the upper face, the edge portions of the abradingsheet between the folded flaps terminating substantially at theremaining substantially straight edge portions, and separate clampingdevices mounted upon the upper face of the disc and engaging the flapportions to clamp them against said upper face.

References Cited in the file of this patent UNITED STATES PATENTS528,024 Perry Oct. 23, 1894 577,860 Keighley Mar. 2, 1897 718,154 PineJan. 13, 1903 1,143,725 Reed June 22, 1915 1,353,966 Lorenz Sept. 28,1920 2,127,703 Schwenke Aug. 23, 1938

